Process for the manufacture of aluminum and aluminum alloys



Patented Nov. 24, 19 31 UNITED STATES- PATENI OFFICE" 'ruim nonnn'r naemmn, or srocxnomr, swnnnn PROCESS FOB TEE MANUFACTURE OF ALUMINUM AND ALLOYS No Drawing. Application filed Kay 14, 1930, Serial No. 452,524, and in .Sweden Kay 25, 1929.

The present invention relates to a process for the manufacture of aluminumand aluminum alloys. This process mainly consists in firstly, producing a primary or preliminary alloy of aluminum and tungsten or an aluminum-alloy containing tungsten in the second step aluminum or a high grade aluminum alloy is recovered from this primary tungsten aluminum alloy by separation or precipitalotion e. g. in a mechanical or electrolytical way of the entire tungsten content or part thereof.

Suggestions have been previously made for the manufacture of aluminum by refining 16 primary aluminum alloys; of such processes may be mentioned the production of a copper-silicon-aluminum alloy and its refining by electrolysis in a molten condition.

In comparison with these known processes 20 the production of aluminum or. aluminum alloys over a primary alloy containing tungsten possesses great advantages. In the first instance the use of an admixture of tungsten in the production of high 'grade' aluminum alloys by electrothermic processescauses a much quieter furnace-operation and a smoother reduction. In fact disturbances occur, as is wellknown, in electrothermic processes for the production of aluminum first and foremost owing to the fact, that the alloy, which is produced by the reduction, by reason of its low specific gravity easily remains in the reduction zone. where under the action of the electric arc and the reducing agency of the carbon present it starts to boil, causes disturbances and leads to the formation of carbides, which may easilV choke the furnace.

A tungsten content in the aluminum allov has now to a very high degree proved itself capable to prevent the sa d drawbacks and d fiiculties. Owing to the fact, that tungsten raises to a remarkable degree the specific wei ht of the roduced alloy, the pre ence of the same facilities to a great extent the possibilities'of working w th slag, which protects the alloy, which is. recovered by the reduction process and this has proved to be of vast importance. The use of a. primary alloy with tungsten, content has, however,

t separated.

liquation can be carried put in such a way that only a art of the tungsten content is iquation tests carried out with tungsten-aluminum alloys, with approximately 8% tungsten, have resulted in an aluminum metal with a tungsten content of only about 0.07%. It is. perfectly obvious that the possibility of so completely separating the tungsten means a very great advang A primary aluminum alloy with tungsten content according to the present method is produced suitably in sucha manner. that aluminum oxide or material containing aluminum-oxide' issmelted in an electrical furnace together with a reducing agent, preferably carbon and with the introduction of admixtures, which contain tungsten, e. g.v in the shape of metal, alloy or compound,such as oxide ore; slag forming admixtures may also be added. f

It is of advantage to return the rich tungsten alloy obtained in the ensuing refining process into the process for the purpose of producing the primary alloy; The reduction process is preferablyconducted in such a way, that an alloy with a high aluminum content is obta ned, containing preferably between and of aluminum. The tungsten content may vary froma few percent up to 50% or more. tungsten content of approximately 10 to 30% has proved to produce very good results.

,As an aluminum oxide containing material bauxite may be used. As, however, bauxites mostly contain a large amount of iron, and .iron is a very undesirable component in the aluminum. as a rule bauxite which in some way or other. e. g. by somereduction smelting process,-has been freed irpn'and possibly also other impurities, is

used.

The purification of the bauxite from silica is, however, not so essential, because 1n certain instances a silicon content in 'thepri mary alloy means an advantage in the refining treatment. n It has been found suitable to subject the primary aluminum alloy to a liquefying treatment. The alloy is accordingly cooled down and kept for a certain time at such a temperature, that those alloys with a'higher smelting point are solidified and can be separated from the remaining allov, which remains in a molten condition. The high speing-point have in this respect proved to facilitate greatly the separation of tungsten from aluminum alloys containing the same.

After the solidification of the tungsten aluminum alloy, the same is separated from the remaining metal bath by centrifugation,

primary alloy under a vacuum at such a ,temperature. that the aluminum is distilled away.

What I claim is:

1. A process for the manufacture of aluminum and aluminum alloys from aluminumoxide and aluminum-oxide containing materials consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treatment a tungsten aluminum alloy and separatiiig fimthis alloy by cooling a tungsten freed'aluminum and leaving a tungsten aluminum alloy in a solidified state, which is enriched. in tungsten.

2. A process for the manufacture of 'alumi num and aluminum alloys from aluminum oxide and aluminum-oxide containing substances consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treatment a tungsten aluminum alloy and producing from thisalloy "by cooling and liquefyinga practically pure a uminum and a tungsten aluminum alloy with a higher percentage of tungsten.

3. A process for the manufacture of aluminum and aluminum alloys from aluminumoxide and aluminum-oxide containing materials consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treatment a tungsten aluminum alloy and producing from this alloy The re-' fining can also be carried out by heating the Leeann by cooling an alloy with a high percentage 'cific gravity of tungsten and its high meltof aluminum and leaving in a solidified state an alloy with a higher percentage of tungsten.

5. A process for the manufacture of aluminum and aluminum alloys from aluminumoxide containing substances consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treatment a tunsstenaluminum alloy and producing from, this alloy by cooling and pressing a tungsten freed alloy with a higher percentage of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten.

6. A process for the manufacture of aluminum and aluminum alloys from aluminum oxide containing substances consisting'in first producing from the same under the addition of'tungsten containing substances by means of an electrothermic reducing smeltingv treatment a tungsten aluminum alloy, which contains up to about 50% tungsten and producing from this alloy by cooling and liquefving a tungsten freed'alloy with a high percentage of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten.

7. A process for the manufacture of aluminum and aluminum alloys from aluminumoxide containing materials consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treatment a tungsten aluminum alloy, which contains between to tungsten and producing from this alloy by cooling and liquefying an alloy with a high percentage of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten.

I 85A process for the manufacture of aluminum and aluminum alloys from aluminum oxide containing materials consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treatment a tungsten aluminum alloy, producing from this-allow by cooling and liquefying an alloy with a high percentage of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten and subjecting the former alloy to an electrolytical producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treat ment a tungsten aluminum alloy producingfrom this alloy by cooling and liquefying an alloy with a high percentage of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten and recovering from the former alloyx the aluminum by distillation. 7

10. A process for the manufacture of aluminum and aluminum alloys from aluminum-oxide containing materials consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducmg smelting treatment a tungsten aluminum alloy, producing from this alloy by cooling and liquefying an alloy with a high percentage of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten and recovering from the former alloy the aluminum by distillation in a vacuum.

' 11. A process for the manufacture of aluminum and aluminum alloys from aluminumoxide containing materials consisting in first producing from the same under the addition of tungsten containing substancesby means of an electrothermic reducing smelting treatment a tungsten aluminum alloy separating from this alloy by cooling a tungsten freed aluminum, leaving a tungsten aluminum alloy with a higher percentage of tungsten in a solidified state and returning the tungsten containing product in. the process as admixture for the production of the first tungsten aluminum alloy.

12. A process for the manufacture of aluminum and aluminum alloys from aluminumoxide containing materials consisting in first producing from the same under the addition oftungsten containing substances byineans of an electrothermic reducing smelting treatment a tungsten aluminum alloy, producing from this alloy by cooling and liquefying an alloy with a high percentage of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten and returning the tungsten containing product in the process as admixture for the production of the first tungsten aluminum alloy.

13. A process for the manufacture of aluminum and aluminum alloys from aluminunr oxide containing materials consisting in first producing from the same under the additi )n l of tungsten containing substances by means of anelectrothermicreducing smelting treatment a tungsten aluminum alloy and pro- :ducingfrom this alloy by cooling and centrifugation an alloy with a high percentage of aluminum and a tungsten aluminum with ahigher percentage of tungsten and returning the tungsten containing product in the process as admixture for the production of the first tungsten aluminmn-alloy.

14 A process for the manufacture of aluminum and aluminum alloys from aluminumoxide containing materials consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smeltingtreatment a tungsten aluminum alloy and producing from this alloy by cooling and pressing an alloy witha high percentage of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten and returning the tungsten containing product inthe process as admixture for the production of the first tungsten aluminum-alloy.

15. A process for the manufacture of aluminum and aluminum alloys from aluminumoxide containing materials consisting in first producing from the same under the addition of tungsten containing substances by means of an electrot-hermic reducing smelting treatment a tungsten aluminum alloy, which contains up to about, 50% tungsten,- producing and a tungsten aluminum alloy with a higher high percentage of aluminum percentage of tungsten andreturning the tungsten containing product in the process as admixture forthe production of the first tungsten aluminum alloy.

16. A process for the manufacture of aluminum and aluminum alloys from aluminumcxide containing materials consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treatment a tungsten aluminum alloy, which contains between 10 to 30% tungstemproducing from this alloy by cooling and liquefving an alloy with a high percentage of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten and returning the tungsten containing product in the process as admixture for the production of the first tungstenaluminum alloy.

17. A process for the manufacture of aluminum and aluminum alloys from aluminum-oxide containing materials consisting in first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treatment a tungsten aluminum alloy, producing from this alloy by cooling and liquefying analloy with a high percentage of aluminum and a tungsten aluminum alloy with a higher, percentage of tungsten, subj ecting'theformer alloy with the high percentage of aluminum to an electrolytical refining treatment and returning the tungsten containing product in the process as admlxture for the production-oi the first tungsten aluminum alloy. r

18. A process for the manufacture of aluminum and aluminum alloy from aluminumox1de containing materlals conslsting 1n first producing from the same under the addition of tungsten containing substances by means of an electrothermic reducing smelting treatment a tungsten aluminum alloy, producing from this alloy by cooling and liquefying an alloy -with a higher percenta28 of aluminum and a tungsten aluminum alloy with a higher percentage of tungsten, re-

covering from the former alloy the aluminum by distillation and returning the tungsten containing product in the process as ad.-'

mixture for the production of the first tungsten aluminum alloy.

19. A process for the manufacture of aluminuin and aluminum allovs from aluminum-oxide containing materials consisting in first producin from -the same under the addition of tung. en containing substances by means of an electrothermic reducing smel" ing treatment a tungs en aluminum alloy.z

producing from this alloy bv cooling and liquefying an alloy with a high percentage of aluminum anda tungsten aluminum alloywith a higher percentage of tungsten, recovering fromthe alloy the aluminum b v distillation in a vacuum and returning the tungsten con aining product in the process as admixture for the production of the first tungsten aluminum alloy.

In testimonv hereof I nflii m'v signature TUBE ROBERT HAGLUND.

i assume 

